1. Fields of the Invention
The present invention relates to a treadmill, and more particularly, to a treadmill which offers buffering effect during the walking exercise while the curved extent of the support plate can be counteracted.
2. Description of the Prior Art
FIG. 1 shows a side view of a conventional treadmill 10 having a handrail 15, a sloping base frame 12 on both ends of which two rollers 16 are mounted. A support plate 14 is disposed on both rollers 16 and is screwed with a plurality of buffer pieces 13 at the side thereof so that the support plate 14 is indirectly fixed on the base frame 12. Thereafter, a walking belt is disposed around both rollers 16 and the support plate 14.
When the operator walks on the treadmill, the feet exert pressure on the walking belt 11 for a cyclic movement. While the support plate 14 is pressed down, the buffer pieces 13 are simultaneously pressed downward. Therefore, the loading of the support plate 14 can be divided; meanwhile, a reactive force for cushioning is created in order to avoid the exercise injury of the feet.
Most of the loading of the support plate 14 is concentrated in the middle thereof so that the middle part thereof is easily crooked and deformed. However, the buffer pieces 13 at the side of the support plate 14 can""t effectively reduce or even remove the concentrating stress, thereby deforming or breaking the support plate 14. On the other side, the buffer pieces 13 can be broken, thereby being separated from the support plate 14. Accordingly, the service life of the treadmill 10 is reduced.
It is a primary object of the present invention to eliminate the above-mentioned drawbacks and to provide a treadmill whose support elements replace the conventional buffer device and are indirectly fixed to the bottom of the base frame, thereby offering buffering effect at the middle place of the support plate.
It""s another object of the present invention to provide a treadmill through which the injuries of feet during exercise session are avoided and the service life of the treadmill is prolonged.
It""s a further object of the present invention to provide a treadmill through which the concentration of stress is reduced or removed.